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Home >> Lexus >> 2017 >> GS 350 F Sport, AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - Diagnostic Codes (4 Of 7) >> SFI System >> DTC P050A-00: Cold Start Idle Control System Performance [09/2016 - 09/2018] >> Procedure
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DTC P050A-00: Cold Start Idle Control System Performance [09/2016 - 09/2018]: Procedure

  1. CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P050A-00) 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine / Trouble Codes.
    5. Read the DTCs.

      Result

      Result Proceed to
      DTC P050A-00 is output A
      DTC P050A-00 and other DTCs are output B

      HINT: 

      If any DTCs other than P050A-00 are output, troubleshoot those DTCs first.

    Result: 

    GO TO DTC CHART. Refer to  DIAGNOSTIC TROUBLE CODE CHART [09/2016 - 09/2017]  , or refer to  DIAGNOSTIC TROUBLE CODE CHART [09/2017 - 09/2018] 

    Result: 

    See step  2

  2. READ VALUE USING TECHSTREAM (FUEL TRIM) 

    HINT: 

    Calculate the total fuel trim values to check the characteristic deviation of the mass air flow meter sub-assembly.

    1. Connect the Techstream to the DLC3.
    2. Start the engine.
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine / Data List / Short FT B1S1, Long FT B1S1, Short FT B2S1 and Long FT B2S1.
    5. Read the values displayed on the Techstream at engine idle.
    6. Add together the Short FT B1S1 and Long FT B1S1 values, and the Short FT B2S1 and Long FT B2S1 values to obtain the total fuel trim.

      Standard

      Total of the Short FT B1S1 and Long FT B1S1 values, and total of the Short FT B2S1 and Long FT B2S1 values is between -20% and 20%.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  5

    Result: 

    OK 

    See step  3

  3. INSPECT THROTTLE BODY WITH MOTOR ASSEMBLY (THROTTLE VALVE) 
    1. Check that there are no deposits around the throttle valve and throttle valve condition.

      OK

      No deposits around the throttle valve and throttle valve moves smoothly.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    See step  10

    Result: 

    NG 

    See step  4

  4. REPAIR OR REPLACE THROTTLE BODY WITH MOTOR ASSEMBLY 
    1. Repair or replace the throttle body with motor assembly.

      Refer to REMOVAL [10/2015 - ]

      HINT: 

      Perform "Inspection After Repair" after repairing or replacing the throttle body with motor assembly.

      Refer to INITIALIZATION [10/2015 - 09/2018]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  15

  5. CHECK PCV SYSTEM 
    1. Check the PCV hose connections.

      Refer to COMPONENTS [10/2015 - ]

      OK

      PCV valve and hose are connected correctly and are not damaged.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  14

    Result: 

    OK 

    See step  6

  6. CHECK INTAKE SYSTEM 
    1. Check the intake system for vacuum leaks.

      Refer to ON-VEHICLE INSPECTION [10/2015 - ]

      OK

      No leaks from the intake system.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  13

    Result: 

    OK 

    See step  7

  7. CHECK AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY 
    1. Visually check that the air cleaner filter element sub-assembly is not excessively contaminated with dirt or oil.

      OK

      The air cleaner filter element sub-assembly is not excessively contaminated with dirt or oil.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  12

    Result: 

    OK 

    See step  8

  8. PERFORM ACTIVE TEST USING TECHSTREAM (OPERATE CAM TIMING OIL CONTROL SOLENOID ASSEMBLY) 
    1. Operate the VVT system through the Active Test, and check if the VVT system is operating normally.
      1. Perform the Active Test, referring to DTC P0011-00 Procedure (VVT system for intake camshaft).

        Refer to DTC P0011-00: Camshaft Position "A" - Timing Over-Advanced or System Performance Bank 1; DTC P0012-00: Camshaft Position "A" - Timing Over-Retarded Bank 1; DTC P0021-00: Camshaft Position "A" - Timing Over-Advanced or System Performance Bank 2; DTC P0022-00: Camshaft Position "A" - Timing Over-Retarded Bank 2 [09/2016 - 09/2018]

      2. Perform the Active Test, referring to DTC P0014-00 Procedure (VVT system for exhaust camshaft).

        Refer to DTC P0014-00: Camshaft Position "B" - Timing Over-Advanced or System Performance Bank 1; DTC P0015-00: Camshaft Position "B" - Timing Over-Retarded Bank 1; DTC P0024-00: Camshaft Position "B" - Timing Over-Advanced or System Performance Bank 2; DTC P0025-00: Camshaft Position "B" - Timing Over-Retarded Bank 2 [09/2016 - 09/2018]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  11

    Result: 

    OK 

    See step  9

  9. READ VALUE USING TECHSTREAM (MASS AIR FLOW SENSOR) 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Powertrain / Engine / Data List / Engine Speed, Mass Air Flow Sensor and Coolant Temperature.
    5. Allow the engine to idle until Coolant Temperature reaches 75°C (167°F) or higher.
    6. Read Mass Air Flow Sensor with the engine speed at 3000 rpm.

      Standard

      Techstream Display Condition Specified Condition
      Mass Air Flow Sensor Engine warmed up
      Shift lever position: P
      A/C: Off
      Engine Speed: 3000 rpm
      Between 10.6 gm/sec and 15.8 gm/sec

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  16

    Result: 

    OK 

    See step  10

  10. CHECK WHETHER DTC OUTPUT RECURS (DTC P050A-00) 
    NOTE:

    In this operation, the engine must be cold (approximately the same as the engine coolant temperature recorded in the freeze frame data).

    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Clear the DTCs.
    5. Turn the engine switch off and wait for at least 30 seconds.
    6. Turn the engine switch on (IG).
    7. Turn the Techstream on.
    8. Enter the following menus: Powertrain / Engine / Data List / Coolant Temperature.
    9. Check that the engine coolant temperature is between -10 and 50°C (14 and 122°F).
    10. Start the engine and warm it up until the engine coolant temperature is the same as the engine coolant temperature in the freeze frame data.
    11. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
    12. Enter the following menus: Powertrain / Engine / Utility / All Readiness.
    13. Input the DTC: P050A-00.
    14. Check the DTC judgment result.

      Result

      Result Proceed to
      NORMAL
      (DTCs are not output)
      A
      ABNORMAL
      (DTC P050A-00 is output)
      B

    Result: 

    CHECK FOR INTERMITTENT PROBLEMS. Refer to  CHECK FOR INTERMITTENT PROBLEMS [10/2015 - ] 

    Result: 

    See step  16

  11. CHECK AND REPAIR VVT SYSTEM 
    1. Check and repair the VVT system.

      HINT: 

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  15

  12. REPLACE AIR CLEANER FILTER ELEMENT SUB-ASSEMBLY 
    1. Replace the air cleaner filter element sub-assembly.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  15

  13. REPAIR OR REPLACE INTAKE SYSTEM 
    1. Repair or replace the intake system.

      HINT: 

      Perform "Inspection After Repair" after repairing or replacing the intake system.

      Refer to INITIALIZATION [10/2015 - 09/2018]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  15

  14. REPAIR OR REPLACE PCV HOSE 
    1. Repair or replace the PCV valve or hose.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  15

  15. CHECK WHETHER DTC OUTPUT RECURS (DTC P050A-00) 
    NOTE:

    In this operation, the engine must be cold (approximately the same as the engine coolant temperature recorded in the freeze frame data).

    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Clear the DTCs.
    5. Turn the engine switch off and wait for at least 30 seconds.
    6. Turn the engine switch on (IG).
    7. Turn the Techstream on.
    8. Enter the following menus: Powertrain / Engine / Data List / Coolant Temperature.
    9. Check that the engine coolant temperature is between -10 and 50°C (14 and 122°F).
    10. Start the engine and warm it up until the engine coolant temperature is the same as the engine coolant temperature in the freeze frame data.
    11. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
    12. Enter the following menus: Powertrain / Engine / Utility / All Readiness.
    13. Input the DTC: P050A-00.
    14. Check the DTC judgment result.

      Result

      Result Proceed to
      NORMAL
      (DTCs are not output)
      A
      ABNORMAL
      (DTC P050A-00 is output)
      B

    Result: 

    END 

    Result: 

    See step  16

  16. CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER SUB-ASSEMBLY CONNECTOR CONNECTION) 
    1. Check the connection and terminal contact pressure of connectors and wire harnesses between the mass air flow meter sub-assembly and ECM.

      Refer to ELECTRONIC CIRCUIT INSPECTION PROCEDURE [09/2014 - ]

      HINT: 

      Repair any problems.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  17

  17. CHECK WHETHER DTC OUTPUT RECURS (DTC P050A-00) 
    NOTE:

    In this operation, the engine must be cold (approximately the same as the engine coolant temperature recorded in the freeze frame data).

    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Clear the DTCs.
    5. Turn the engine switch off and wait for at least 30 seconds.
    6. Turn the engine switch on (IG).
    7. Turn the Techstream on.
    8. Enter the following menus: Powertrain / Engine / Data List / Coolant Temperature.
    9. Check that the engine coolant temperature is between -10 and 50°C (14 and 122°F).
    10. Start the engine and warm it up until the engine coolant temperature is the same as the engine coolant temperature in the freeze frame data.
    11. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
    12. Enter the following menus: Powertrain / Engine / Utility / All Readiness.
    13. Input the DTC: P050A-00.
    14. Check the DTC judgment result.

      Result

      Result Proceed to
      ABNORMAL
      (DTC P050A-00 is output)
      A
      NORMAL
      (DTCs are not output)
      B

    Result: 

    END 

    Result: 

    See step  18

  18. CHECK HARNESS AND CONNECTOR (MASS AIR FLOW METER SUB-ASSEMBLY - ECM) 
    1. Disconnect the mass air flow meter sub-assembly connector.
    2. Disconnect the ECM connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      F39-5 (VG) - F74-116 (VG) Always Below 1 Ω
      F39-4 (E2G) - F74-115 (E2G) Always Below 1 Ω
      F39-5 (VG) or F74-116 (VG) - Body ground and other terminals Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  19

  19. REPLACE MASS AIR FLOW METER SUB-ASSEMBLY 
    1. Replace the mass air flow meter sub-assembly.

      Refer to REMOVAL [10/2015 - ]

      HINT: 

      • If the results of the inspections performed in step 9 indicated no problem, proceed to the next step without replacing the mass air flow meter sub-assembly.
      • Perform "Inspection After Repair" after replacing the mass air flow meter sub-assembly.

        Refer to INITIALIZATION [10/2015 - 09/2018]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  20

  20. CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED 

    HINT: 

    In this operation, the engine must be cold (approximately the same as the engine coolant temperature recorded in the freeze frame data).

    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Clear the DTCs.
    5. Turn the engine switch off and wait for at least 30 seconds.
    6. Turn the engine switch on (IG).
    7. Turn the Techstream on.
    8. Enter the following menus: Powertrain / Engine / Data List / Coolant Temperature.
    9. Check that the engine coolant temperature is between -10 and 50°C (14 and 122°F).
    10. Start the engine and warm it up until the engine coolant temperature is the same as the engine coolant temperature in the freeze frame data.
    11. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
    12. Enter the following menus: Powertrain / Engine / Utility / All Readiness.
    13. Input the DTC: P050A-00.
    14. Check the DTC judgment result.

      Result

      Result Proceed to
      NORMAL
      (DTCs are not output)
      A
      ABNORMAL
      (DTC P050A-00 is output)
      B

    Result: 

    END 

    Result: 

    REPLACE ECM. Refer to  REMOVAL [10/2015 - ]